It was an act of pure evil. Josh Powell deliberately blew up his house, killing himself and his two young sons in a fiery 2012 explosion that shocked the nation.
In a 911 call, Josh said, "Hello, this is Josh, and I'm calling to say goodbye."
He was the only suspect in the disappearance of his wife, Susan, whose body has never been found.
Now, we're learning new details about Josh Powell in the just-released book If I Can't Have You by journalists Gregg Olsen and Rebecca Morris.
Olsen told INSIDE EDITION, "It starts as a missing person and it ends up being an American tragedy of unbelievable proportion."
The authors say he abused his boys and even kept Susan from giving them enough to eat.
Olsen said, "He didn't give her money for food so that she had to go borrow food from neighbors. And the boys were thin and they were not getting the nutrition they needed because their father wanted to control everything they did, everything they ate."
The boys suffered deep emotional scars. Olsen details what their grandfather, Chuck Cox, Susan's dad, said he witnessed.
"He came into the bathroom when they were in the bathtub and one of the boys was holding the other kid's head under the water. And Chuck was absolutely sure if he hadn't intervened that boy would have drowned," said Olsen.
Susan seemed to sense something terrible was going to happen. She made a haunting video more than a year before she disappeared in 2009, where she said, "Hope everything works out and we live happily ever after, as much as that's possible."
She spoke about her husband's violent temper, saying, "He got in a rage because I broke this. And threw all my DVD's and made a mess because he was angry with me from a year or two back."
The authors speculate that Josh poisoned Susan. On the night she disappeared he cooked a special pancake dinner just for her.
Olsen said, "Whatever was in that pancake, we'll never know, but it made her violently ill and she went to bed early that night."
Josh told police that he took his sons on a camping trip in the middle of the night during a snowstorm and when they returned home, Susan was gone. His story was met with disbelief, but cops found no proof of a crime.
Now, the authors say Josh and his brother, Michael, who committed suicide in 2013, secretly disposed of Susan's body.
"A lot of people believe the body is somewhere in the desert. In fact, one of the little boys told a family member that he had seen his mother in a cave," Olsen stated.
And what about Josh's father, Steven Powell, who was so obsessed with Susan that he wrote a creepy love song to her with the lyrics: "I can love you in a secret way. I can love you each and every day."
Olsen told INSIDE EDITION, "He was writing all these fantasies about Susan and how much he loved her and how much he wanted to have sex with her and he was sending her naked pictures. He was doing all this crazy stuff that none of us could ever have imagined was ever going on."
Steven Powell was recently released from prison following a nearly two year sentence on a child pornography conviction. The authors say he may now be the only one alive who knows what really happened to Susan Powell.
To read an excerpt from the book, click on the Download PDF button below.